You don't have to drink 8 glasses of water a day anymore

Ally Hirschlag is a producer/actor/writer who lives in Brooklyn, NY and buys way too many toys for her cats. She contributes to several publications, including Bustle, and The Nerve, and enjoys writing about all things woman. In her spar...

The gallon-of-water-a-day rule is a myth, says science

You've probably seen people who carry around those giant, gallon-size water bottles that don't fit into any bag. You may have even wondered if they've figured out something about water intake that you haven't.

Extreme health consciousness has been on the rise, especially in the past 10 years, and with that has come a greater focus on how much water we consume every day. One idea that has persisted among the hyper-health-conscious is that we need to drink eight glasses of water a day, which is roughly the equivalent of 1 gallon of water.

However, if that sounds like a ridiculously large amount of water to put into your body on a daily basis, you're right. It turns out the eight-glasses-of-water-a-day rule is in fact a myth and should be disregarded as necessary to keep hydrated.

Professor of pediatrics and health writer Aaron E. Carroll helped co-author a paper on the subject that was published in the BMJ back in 2007. The paper focused on medical myth-busting, and excessive daily water intake was right at the top. Sadly, while the paper got a great deal of attention at the time it was published, it did very little to change people's perception of water intake in the long run.

Carroll believes the myth came out of a 1945 Food and Nutrition Board recommendation, which stated we need to be drinking 2.5 liters of water a day. However, what failed to carry over from this was the following sentence: “Most of this quantity is contained in prepared foods.” We get a great deal of water from the food we eat and other beverages we drink. Even things like beer and coffee, which people often claim dehydrate you (another proven myth), are predominantly water.

Essentially, we're not giving our bodies enough credit for the jobs they do on their own without our help. We are actually designed to feel thirsty long before we're dehydrated to help prevent us from threatening our physical health.

My own experience with water was a fickle one until I went to Burning Man last year. My mom was always telling me to "drink more water," and thus I used to think I was never getting enough, despite the fact that I felt perfectly hydrated. However, when I went into the Nevada desert for a week and was told I had to drink a gallon of water to prevent dehydration due to the severe climate, I listened. The interesting thing I took from that experience was that I didn't have to make myself drink water — my body did exactly what Dr. Carroll says it should do — it alerted me when I was thirsty, and I drank. The difference was that in the desert, you just naturally drink close to a gallon a day because your body requires it in that dry heat.

So the moral of the story is, listen to your body, because dehydration is real, but stop wasting money on all those giant water bottles, because the eight-glasses-a-day rule is not.